/* 读取 struct input_event 类型数据 */
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/input.h>

int main(int argc, char *argv[])
{
    struct input_event in_ev = { 0 };
    int fd = -1;
    /* 校验传参 */
    if (2 != argc) {
        fprintf(stderr, "usage: %s<input-dev>\n", argv[0]);
        exit(-1);
    }
    /* 打开文件 */
    if (0 > (fd = open(argv[1], O_RDONLY))) {
        perror("open");
        exit(-1);
    }

    for (;;) {
        /* 循环读取数据 */
        if (sizeof(struct input_event) != 
            read(fd, &in_ev, sizeof(struct input_event))) {
                perror("read");
                exit(-1);
        }
        /* 打印数据 */
        printf("type: %d, code: %d, value: %d\n", 
            in_ev.type, in_ev.code, in_ev.value);
    }
}